Disclosed herein is a method for treating carbon black, and more specifically, a method for surface treating carbon black with a polyhedral oligomeric silsesquioxane, and a carbon black material prepared by the method.
As one of the top 50 industrial chemicals produced worldwide, carbon black is used in a number of different industrial applications. Approximately 8.1 million tons of carbon black is produced annually, and it is the most commonly used conductive agent used in plastics, coatings, toners and printing inks. Although there is great demand for carbon black in materials production, it suffers from a percolation threshold which can greatly affect the conductivity of the material. The percolation threshold relates subtle changes in carbon black concentration to a dramatic change in conductivity. Due to this effect, materials can go from being conductive to being resistive by varying the concentration of carbon black ever so slightly, for example, less than 1 weight percent variation. For electrically conductive materials, a significant amount of carbon black may be required in order to achieve the conductivity necessary for a given material, which can diminish the strength of the materials. For materials which require a specific conductivity, such as intermediate transfer belts and bias charge rollers, this can be problematic from an electronic and mechanical standpoint. There are many types of carbon blacks of various particle size and physical properties, which offer different ranges of conductivity. However, each of these carbon blacks typically suffers from the same percolation issue.
Currently available methods for preparing carbon black are suitable for their intended purposes. However, a need remains for an improved system and method that is suitable for treating carbon black. A need also remains for an improved method for treating carbon black materials which can tailor the conductivity in the range difficult to achieve by pure, untreated carbon black. Further, a need remains for a method for treating carbon black to control the percolation threshold and enable use of lower concentrations of carbon black. Still further, a need remains for an improved method for treating carbon black materials which can tailor the conductivity in the range previously available only with more expensive materials.
The appropriate components and process aspects of the each of the foregoing U.S. Patents and Patent Publications may be selected for the present disclosure in embodiments thereof. Further, throughout this application, various publications, patents, and published patent applications are referred to by an identifying citation. The disclosures of the publications, patents, and published patent applications referenced in this application are hereby incorporated by reference into the present disclosure to more fully describe the state of the art to which this invention pertains.